1. When a synchronous motor is at working condition, is there induced electromotive force in the rotor's winding? Is there induced electromotive force in the rotor's winding when we start up the synchronous motor? Why? 2. If the frequency of the input voltage is adjustable, what is the rotation speed of a 6-pole synchronous motor when the input frequency is 50Hz and 40Hz, respectively?

1. When a synchronous motor is at working condition, is there induced electromotive force in the rotor's winding? Is there induced electromotive force in the rotor's winding when we start up the synchronous motor? Why? 2. If the frequency of the input voltage is adjustable, what is the rotation speed of a 6-pole synchronous motor when the input frequency is 50Hz and 40Hz, respectively?

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter33: Single-phase Motors

Section: Chapter Questions

Problem 17RQ

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